alexx933 Posted September 14, 2014 Share Posted September 14, 2014 Hi guys, I have just been stationed down in Florida at Tyndall AFB and had my car shipped down here. Won't ever do that again. Running a stock 1981 turbo engine. I've been wanting to install a boost controller and run about 10lbs. I have no intercooler, just the stock j-pipe. I have had a boost gauge for a while just to monitor the engine. For the past year and 3-4 months, my engine has only been hitting about 6lbs of boost. I haven't thought too hard on it because it seems to run strong. This past week, I ran around to build my boost controller from hardware stores and finally got it together. After waiting out the rain for the past few days, the controller was installed today. Ran the lines into the cabin so that I could adjust it easier. I left base and set off down the road with the adjusting screw almost all the way out so that I was at base boost. The first pull was at WOT. The z went just like normal until at full boost. Then, it sputtered and stopped accelerating hard. I eased off the gas and it pulled hard in a specific position. After a couple more tries. The same thing kept repeating. I adjust the boost higher without any change at all. The screw was fully in to make the boost as high as possible. I still only could hit about 6lbs. Personally, I'd rather be able to maintain full function of my throttle than have "higher" boost. Even though I never went over stock levels. So I turned around to uninstall the controller. Currently, she is cooling down so I don't burn myself. Any thoughts as to why this is happening? This should be a very simple procedure. Thanks! Quote Link to comment Share on other sites More sharing options...
mtnickel Posted September 15, 2014 Share Posted September 15, 2014 Hi guys, I have just been stationed down in Florida at Tyndall AFB and had my car shipped down here. Won't ever do that again. Running a stock 1981 turbo engine. I've been wanting to install a boost controller and run about 10lbs. I have no intercooler, just the stock j-pipe. I have had a boost gauge for a while just to monitor the engine. For the past year and 3-4 months, my engine has only been hitting about 6lbs of boost. I haven't thought too hard on it because it seems to run strong. This past week, I ran around to build my boost controller from hardware stores and finally got it together. After waiting out the rain for the past few days, the controller was installed today. Ran the lines into the cabin so that I could adjust it easier. I left base and set off down the road with the adjusting screw almost all the way out so that I was at base boost. The first pull was at WOT. The z went just like normal until at full boost. Then, it sputtered and stopped accelerating hard. I eased off the gas and it pulled hard in a specific position. After a couple more tries. The same thing kept repeating. I adjust the boost higher without any change at all. The screw was fully in to make the boost as high as possible. I still only could hit about 6lbs. Personally, I'd rather be able to maintain full function of my throttle than have "higher" boost. Even though I never went over stock levels. So I turned around to uninstall the controller. Currently, she is cooling down so I don't burn myself. Any thoughts as to why this is happening? This should be a very simple procedure. Thanks! Do you have a diagram of the boost controller you built? My Initial reaction is that perhaps you built a ball/spring type boost controller but failed to put in a relief hole on the waste gate side. Here's what I mean: Notice the line in the middle "1/16" bleeder hole". Did you happen to make sure you put this into your boost controller? If not, then what can happen is that you build boost (say when you go WOT), then once the boost pushes the ball and gets to the wastegate the boost starts to drop. The issue is that once that ball closes again you have pressure stuck between the ball and your waste gate permanently holding it open = no boost. Check that, and if you don't have a relief, drill a 1/16" hole somewhere on the waste gate side of the lines. Quote Link to comment Share on other sites More sharing options...
alexx933 Posted September 15, 2014 Author Share Posted September 15, 2014 I have a diagram in the car. I will take a picture of the controller and diagram later tonight. The t-fitting used has been drilled for a vent. I don't think that was/is the issue. I could stop after boost and rebuild it. My car already runs rich so I doubt there is a fuel issue either. Quote Link to comment Share on other sites More sharing options...
Tony D Posted September 15, 2014 Share Posted September 15, 2014 You plug the emergency relief valve in the intake manifold? Quote Link to comment Share on other sites More sharing options...
alexx933 Posted September 15, 2014 Author Share Posted September 15, 2014 I haven't plugged that as I read that the emergency relief valve doesn't activate until extremely high boost pressures upwards of 20+ lbs Quote Link to comment Share on other sites More sharing options...
NewZed Posted September 15, 2014 Share Posted September 15, 2014 You plug the emergency relief valve in the intake manifold? That's a good hint. It led me to the most likely answer. I looked in what is probably the most reliable resource. Quote Link to comment Share on other sites More sharing options...
alexx933 Posted September 16, 2014 Author Share Posted September 16, 2014 I may have misunderstood the pressures required to make the relief valve open when I originally read the manual trying to identify it. I was reading this earlier today at work and was wondering the conversion for kPa to psi. Just looked it up. The turbo supplement says the valve opens between 42.7 and 50.7 kPa. Found a conversion calculator and that equals 6.19 to 7.35 psi. Had I done this sooner I might not need a post haha Sorry for making another pointless thread! Thanks though! Quote Link to comment Share on other sites More sharing options...
Tony D Posted September 16, 2014 Share Posted September 16, 2014 Is that kPaA or kPaG? Keep in mind the stock map stops at 10psi(g)... Quote Link to comment Share on other sites More sharing options...
alexx933 Posted September 16, 2014 Author Share Posted September 16, 2014 Tony, the supplement doesn't specify. Nor did the calculator. I'm not even sure what the A and G stand for... So I'm assuming it was talking about plain kPa. 10psi was as high as I wanted to go. She is my only car at the moment so I'd rather not blow the engine! I actually just read another of your posts in which you stated the limitations for the stock maps. I want to say it was one of Ben's z's posts. Needless to say I had myself a laugh after you told him off. As far as brass plugs go, other posts, such as this, say a brass plug will work. I should be able to find one at home depot. This should be exactly what I need right? No special threads needed? Quote Link to comment Share on other sites More sharing options...
Tony D Posted September 16, 2014 Share Posted September 16, 2014 Absolute or Gauge. The reason I mention it is because most engines will idle between 35-50 kPa(A) while the relief valve is set to go at 43-51 kPa(G).... which is actually 143-151 kPa(A). A Brass Plug will shine up nicely. NPT worked for me, with a sealant (Loctite 567) and turned in 1/4 turn past finger tight and let the sealant set up for an hour or two. That lets you take it back out with a propane torch and a reasonable sized crescent wrench later on... If you got 1/2 turn it's in there, and you will need to heat it, and use an 18" wrench to get it out later...while it's clamped in a vise! Loctite 567 in miracle sealant. Quote Link to comment Share on other sites More sharing options...
alexx933 Posted September 16, 2014 Author Share Posted September 16, 2014 Holy crap haha that takes some effort! That thread sealant better be worth it's price tag though! $4.25 for 6ml is pretty steep for an E1... I think I will find a silver plug or paint it silver to blend in a little more. My stock intake is pretty cluttered as is. I appreciate the help! I like how you don't always give the answer. You make people think a little bit so they truly understand it better. Quote Link to comment Share on other sites More sharing options...
Tony D Posted September 16, 2014 Share Posted September 16, 2014 What's an E1 make these days? I remember when it was $647.47... That question thing I can attribute to TSgt Cox at FTD 911, Kadena AB Japan. There were guys who absolutely hated him as well because of that method of answering questions in the FTD Class. Oh, how I miss those classes, it was always fun to be one of "the initiated" who knew "there will always be one" and we would find it out on the first day of class when TSgt Cox would start the electrical portion of the training, "tracing circuits" and he would reach for a marker and say "So we start with the Battery Circuit, and for that I'll use Green..." Someone invariably would say "But the Battery Circuit is Red." He would look at the initiated in the class with the look of "We have 'the one' in this class identified!" and say: Why? "Because the Battery Circuit is RED!" We would all look at each other...sniggering and nod "Yep, this guy will be the one..." and would sit back as TSgt Cox would get irrefutable logic of "BECAUSE" as to why the battery circuit would be red. I digress... As for a silver plug, galvanized steel will do, and a Stainless Plug you might find a bit pricey. I have found internally - wrenched (big hex) Brass Plugs that go in close to flush. Painting the whole manifold will make whatever you choose a moot point.... it's all the same when a coat of paint is on it! Quote Link to comment Share on other sites More sharing options...
Tony D Posted September 16, 2014 Share Posted September 16, 2014 Don't you raid government bench stock at the AGE Shop there in Tyndall?..... Quote Link to comment Share on other sites More sharing options...
alexx933 Posted September 17, 2014 Author Share Posted September 17, 2014 I average about $550 take home per check. Not the greatest lol but I put on my first stripe on the 18th! I'd rather not remove my manifold again haha I had quite a few issues when my exhaust gasket blew. So no paint for me in the near future. and no plugs in our bench stock haha But I am very seriously considering trading my z for a 91 240sx with an rb20 tomorrow. I'm ready to switch gears on my project. I love my z but I lack the skill set/resources required to repair it and finish it how I'd like to. A fair bit of rust and possible bent suspension on my car combined with a very clean install on the 240sx is pushing me to trade. BUT I love my car and would hate to see her go. It's tough to decide. Everybody complains of the regret about getting rid of a z. Quote Link to comment Share on other sites More sharing options...
Tony D Posted September 17, 2014 Share Posted September 17, 2014 I was using gross numbers.... I meant for sealants. They're not DIFM so no possible issues. There was a time during the diesel conversion that the MJ1 Bomblifts used Holley Red Pumps as the boost to the main. They were not DIFM, either. The vanes would go out and you just replaced the pump. AF Form 1000 was submitted and rejected to use the vane kit in them. So I happily took all those Holley Red's and put a vane kit in them, along with brushes and resold them to the Japanese. Knowing when "your crate of scrap" is clearing DPDO was really helpful (I guess thats DRMO now...) If you think $4 for sealant is too much, an RB20 will be excruciating. Quote Link to comment Share on other sites More sharing options...
alexx933 Posted September 17, 2014 Author Share Posted September 17, 2014 I was joking about the sealant lol I googled it to find a bottle costing $50-60. I'm still on the edge about pulling the trigger tomorrow. Quote Link to comment Share on other sites More sharing options...
Tony D Posted September 17, 2014 Share Posted September 17, 2014 I've always stolen my sealants... Quote Link to comment Share on other sites More sharing options...
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